This invention relates to a synthetic recording device in an automatic performance piano capable of conducting accurate synthetic recording (hereinafter sometimes referred to as "overdubbing") with a simple operation.
There is known an automatic performance piano which reads performance data stored in a storage medium and conducts an automatic performance by driving the keyboard and pedals of the piano in response to the read out information.
FIG. 10 shows an example of construction of a conventional automatic performance piano. In this figure, an automatic performance piano is constructed generally of a grand piano main body 10 and a controller 20. The controller 20 contains an FDD (floppy disk drive) for storing performance data and a CPU (central processing unit) for performing control of the entire automatic performance piano. The grand piano main body 10 is connected to the controller 20 through a cable CA.
In the grand piano main body 10, a pedal 11 is pivotably connected to a pedal support 11a. A push-up rod 11b is pivotably connected to the pedal 11 to move in the vertical direction in an interlocking motion with the pivotal motion of the pedal 11. This push-up rod 11b is connected to a mechanism such as a damper which corresponds to the pedal operation. The push-up rod 11b penetrates a pedal drive solenoid 11c. A plunger (not shown) is provided at a location in the push-up rod 11b opposing the pedal drive solenoid 11c. In the automatic performance mode, a drive current corresponding to the performance data is supplied to the pedal drive solenoid 11c to actuate the plunger which in turn causes the push-up rod 11b to move upwardly.
Each key 12 of a keyboard is pivotably mounted to a ballance pin 12a. An action 12b is connected to each key 12 so that, when the key 12 has been struck, a hammer 12c is rotated to strike a string 12d which is stretched above. A key drive solenoid 12e and a key sensor 12f are respectively provided for each key 12. In the automatic performance mode, a drive current corresponding to the performance data is supplied to the key drive solenoid 12e to drive the key 12.
The operation of the prior art automatic performance piano will be briefly described. In the automatic performance mode, the performance data is sequentially read from the FDD of the controller 20. A playback event is extracted from this performance data and is supplied to the grand piano main body 10 through the cable CA. In the grand piano main body 10, a drive current is supplied to a corresponding one of the key drive solenoid 12e and the pedal drive solenoid 11c in accordance with the playback event and a corresponding one of the keys 12 or the pedals 11 is thereby driven to conduct the automatic performance.
In the write mode, the operation of the key 12 is detected by the key sensor 12f and a corresponding operation event is supplied to the controller 20 through the cable CA. Performance data is produced in the controller 20 on the basis of this operation event and stored in the FDD.
There is a demand for a so-called overdubbing function to the above described automatic performance piano. For realizing this overdubbing, it is conceivable to detect a keyboard operation in the automatic performance mode and effect recording by superposing this operation event and a playback event one upon the other. During overdubbing, however, both an operation due to a playback event and an operation due to performance by a performer are made in the piano main body and, accordingly, operation events corresponding to the performance data and operation events corresponding to the keyboard operation by the performer exist mixedly in operation events detected in the piano main body. For preventing redundant recording of the same performance data, therefore, it is necessary to select only operation events corresponding to the keyboard operation by the performer. Since, however, operation events in the automatic performance piano are generated merely by detecting operation of keys, it is not possible to discriminate operation events corresponding to the performance data from operation events due to the keyboard operation by the performer. For this reason, a sufficiently accurate overdubbing function cannot be realized in the prior art automatic performance piano.
It has also been conceived to divide a keyboard into a key range in which recording is to be made and a key range in which playback is to be made by a setting operation made from outside and transpose performance information for playback by a predetermined amount of transposition by a setting operation made from outside thereby to transfer the range of the keys to be played back from the key range in which recording is to be made. In this method, however, the performer must determine and designate by himself an optimum amount of transposition depending upon conditions such as a range of tones of a music to be played each time an overdubbing is made with a result that operability of the automatic performance piano is deteriorated. Further, if the performer has failed to set the amount of transposition to an optimum amount, an optimum transposition cannot be obtained with resulting occurrence of disharmony in the performance.
It is an object of the invention to provide a synthetic recording device in an automatic performance piano capable of preventing redundant recording of performance data and performing an accurate overdubbing with a simple operation.